Add support to set environment variables to Terraform environment (#7192

)

# Description
Added a function to set environment variables to the Terraform process.
This function reads user provided configuration from the
RecipeConfig/EnvVariables section of the Radius environment
configuration and is invoked during the setup phase for Terraform
deployment.

[link to PR for design
doc](radius-project/design-notes#39)

The design document describes a SecretReference type and ability to
fetch data from secrets and set environment variables. This will be
implemented in subsequent PRs.

## Type of change
- This pull request adds or changes features of Radius and has an
approved issue #6539

Fixes: Part of #6539

---------

Signed-off-by: Vishwanath Hiremath <[email protected]>
Co-authored-by: Vishwanath Hiremath <[email protected]>

pkg/recipes/terraform/execute.go

@@ -88,6 +88,12 @@ func (e *executor) Deploy(ctx context.Context, options Options) (*tfjson.State,
 		return nil, err
 	}
 
+	// Set environment variables for the Terraform process.
+	err = e.setEnvironmentVariables(ctx, tf, options.EnvConfig)
+	if err != nil {
+		return nil, err
+	}
+
 	// Run TF Init and Apply in the working directory
 	state, err := initAndApply(ctx, tf)
 	if err != nil {
@@ -194,6 +200,24 @@ func (e *executor) GetRecipeMetadata(ctx context.Context, options Options) (map[
 	}, nil
 }
 
+// setEnvironmentVariables sets environment variables for the Terraform process by reading values from the environment configuration.
+// Terraform process will use environment variables as input for the recipe deployment.
+func (e executor) setEnvironmentVariables(ctx context.Context, tf *tfexec.Terraform, envConfig *recipes.Configuration) error {
+	if envConfig != nil && envConfig.RecipeConfig.Env.AdditionalProperties != nil {
+		envVars := map[string]string{}
+
+		for key, value := range envConfig.RecipeConfig.Env.AdditionalProperties {
+			envVars[key] = value
+		}
+
+		if err := tf.SetEnv(envVars); err != nil {
+			return fmt.Errorf("failed to set environment variables: %w", err)
+		}
+	}
+
+	return nil
+}
+
 // generateConfig generates Terraform configuration with required inputs for the module, providers and backend to be initialized and applied.
 func (e *executor) generateConfig(ctx context.Context, tf *tfexec.Terraform, options Options) (string, error) {
 	logger := ucplog.FromContextOrDiscard(ctx)

pkg/recipes/terraform/execute_test.go

@@ -21,6 +21,7 @@ import (
 	"testing"
 
 	"github.com/hashicorp/terraform-exec/tfexec"
+	dm "github.com/radius-project/radius/pkg/corerp/datamodel"
 	"github.com/radius-project/radius/pkg/recipes"
 	"github.com/radius-project/radius/pkg/recipes/terraform/config"
 	"github.com/radius-project/radius/test/testcontext"
@@ -114,3 +115,61 @@ func Test_GetTerraformConfig_InvalidDirectory(t *testing.T) {
 	require.Error(t, err)
 	require.Contains(t, err.Error(), "error creating file: open invalid-directory/main.tf.json: no such file or directory")
 }
+
+func TestSetEnvironmentVariables(t *testing.T) {
+	testCase := []struct {
+		name string
+		opts Options
+	}{
+		{
+			name: "set environment variables",
+			opts: Options{
+				EnvConfig: &recipes.Configuration{
+					RecipeConfig: dm.RecipeConfigProperties{
+						Env: dm.EnvironmentVariables{
+							AdditionalProperties: map[string]string{
+								"TEST_ENV_VAR1": "value1",
+								"TEST_ENV_VAR2": "value2",
+							},
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "AdditionalProperties set to nil",
+			opts: Options{
+				EnvConfig: &recipes.Configuration{
+					RecipeConfig: dm.RecipeConfigProperties{
+						Env: dm.EnvironmentVariables{
+							AdditionalProperties: nil,
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "no environment variables",
+			opts: Options{
+				EnvConfig: &recipes.Configuration{
+					RecipeConfig: dm.RecipeConfigProperties{},
+				},
+			},
+		},
+	}
+
+	for _, tc := range testCase {
+		t.Run(tc.name, func(t *testing.T) {
+			ctx := testcontext.New(t)
+			workingDir := t.TempDir()
+
+			tf, err := tfexec.NewTerraform(workingDir, filepath.Join(workingDir, "terraform"))
+			require.NoError(t, err)
+
+			e := executor{}
+
+			err = e.setEnvironmentVariables(ctx, tf, tc.opts.EnvConfig)
+			require.NoError(t, err)
+		})
+	}
+}